Sorry to hear about your illness. I see what you are going through all the time. As an NRA certified pistol instructor in Florida, I have alot of students who are seniors and have arthritis. Many utilize Pachmayer and Hogue grips on their revolvers to help absorb recoil, Hey!!!, there is absolutely nothing wrong with a fine load in a .38 spcl +P or a .38 spcl SWC. I never feel undergunned carrying a Smith J Frame or a Taurus Clone. I always carry extra speed loaders , so I actually have one full cylinder and 2 speedloaders in a double uncle mikes pouch, so thats 15 rds total.
Its funny, I always hear this from new students who take the Florida Concealed Carry Course, ( NRA First Steps or Basic equivalent), that the gun shop owner told them, " you should carry at least a .40SW or a .45ACP), but I always tell the student, "Hey!!, if you can't accurately fire a .40SW or a.45ACP because of muscular or arthritic issues, why have a gun that you can never trully become proficient with?, better a .32H&R or a .38spcl than no gun at all!!!, am I right.!!!??!!!", heck, I carry a 10mm Glock 20 as my primary and back it up with a Smith J Frame, but I am only 38 years old and have my strength, If I had arthritis and similar issues, I would probably carry a revolver due to the dexterity it takes to rack a slide and I would have a nicely loaded .38+P or .38SWC. I wish you all the best, and you did the right thing, no use agrivating your medical condition by firing .357 full house loads and .40SW, better to have a gun that you can be proficient with, then to agrivate yourself physiologically and psychologically. I wish you all the best. You did the right thing.